Figure 1. LPS induced IL-6 secretion and upregulated Nampt expression in MC3T3-E1 cells. (A) CCK-8 results showing that cell proliferation was inhibited when the LPS concentration was above 100 ng/mL. (B) ALP staining and (C) Measurement of ALP activity showing that ALP was decreased on the 7th day after LPS treatment. On day 3 of LPS treatment, (D) Real-time PCR analysis of Nampt and IL-6 mRNA expression normalized to β-actin. (E) Western blot results showing the protein level of Nampt. (F) IL-6 was induced by LPS at varying concentrations, as measured by ELISA. The data are expressed as the mean ± SD. #, p<0.05 vs. LPS 0 ng/mL; ##, p<0.01 vs. LPS 0 ng/mL.